Monthly Archives: November 2015

You must set this property to a non-null value of type ‘System.Int64’.

Recently I encountered following problem in C#.

System.InvalidOperationException was unhandled by user code
Message: The 'Id' property on 'SomeDAO' could not be set to a 'System.Decimal' value. You must set this property to a non-null value of type 'System.Int64'.

1 2	System.InvalidOperationException was unhandled by user code Message: The 'Id' property on 'SomeDAO' could not be set to a 'System.Decimal' value. You must set this property to a non-null value of type 'System.Int64'.

This error is pretty obvious in certain context, but if you don’t read it carefully enough, in some situations you might get… Read more »

Javascript gotcha ! (if you come from Python)

All keys are strings (unlike in Python) Even though this is a basic, got me really hard times debugging my code after writing a lot in python, where this statement… Read more »

What is difference between atan and atan2 ?

In almost every programming language there some sort of math module with various trigonometric functions including functions called atan and atan2. atan(x,y) Now everybody knows atan, it’s just inverse tangent,… Read more »